|I have a NA->TT conversion with the NA rear end the first three gears were really hard to grab grip in. SO I swapped a 3.69 Q45 diff in.
My transmission already had the TT speed sensor, so in addition the speedo is now accurate!
One thing that is super nice is that the cruising RPM is a lot nicer. The 4.10 rear end put me at a bit of a loud spot while going 55.